Diversity and abundance of springtails (Hexapoda: Collembola) in soil under 90-year potato monoculture in relation to crop rotation

The monoculture cropping system causes significant changes within the soil ecosystem, which constitutes a habitat for soil-dwelling springtails. Focusing on the response of soil fauna to 90 years of potato cultivation in monoculture the study investigates the abundance and diversity of soil-dwelling springtails, considering changes in the soil environment in relation to five-crop rotation. Another point was the soil quality evaluation using Collembola as bioindicators (QBS-c index). A long-term monoculture experiment was established in Poland in 1923 and has continued uninterruptedly to the present time. Soil samples were taken over a period of three years (2011–2013) to determine collembolan abundance and composition, as well as physical and chemical soil properties.

The study demonstrated that there were greater numbers of Collembola in the long-term monoculture of potatoes, especially before planting time, compared to numbers in a five-field crop rotation. At the same time apparently greater species diversity was found in potato culture within crop rotation. The biological indicator of soil quality based on the occurrence of springtails (QBS-c) has proved useful in assessing changes in soil caused by agrotechnical activities. This index indicated better biological soil quality in the five-field rotation system compared to monoculture.     

Chilling stress tolerance of two soya bean cultivars: Phenotypic and molecular responses

Chilling stress is a major factor limiting the yield of soya bean [Glycine max (L.) Merr.] on a global scale. However, the regulatory network that controls the chilling response of soya bean remains unclear. In the present study, phenotyping and quantitative analyses of miRNAs in soya bean under chilling stress were carried out to determine the impact of environmental constraints on soya bean productivity. Measurements done during soya bean growth in chilling along with the results of field trials indicated that the cultivars Augusta and Fiskeby V responded differently to low temperatures. Although chilling affected the reproductive development of both cultivars, the final seed output remained unchanged. The differential expression of miR169, miR319, miR397 and miR398 under cold stress was detected using ddPCR. Upon chilling in the reproductive stage, we found that these miRNAs had contrasting expression profiles in Augusta and Fiskeby V. A set of candidate target genes was predicted based on degradome sequencing data. A negative correlation was found between the expression of miR169, miR319 and miR398 and their targets in the roots of both cultivars. Our work elucidates the impact of chilling stress on the productivity of two soya bean cultivars and reveals the importance of miRNA involvement in the low temperature response.     

Thrips (Thysanoptera) associated with two genetically modified types of linseed (Linum usitatissimum L.)

Journal of Plant Diseases and Protection - The aim of this study was to determine thrips abundance, species composition and seasonal dynamics on two genetically modified types of linseed, i.e.,...